


Illuminated

by triggeringthehealing (froggydarren)



Series: FullmoonFiclet Entries [104]
Category: Teen Wolf (TV)
Genre: Blacklight Party, Humor, M/M, UV lights, research spirals
Language: English
Status: Completed
Published: 2018-06-17
Updated: 2018-06-17
Packaged: 2019-05-24 12:15:02
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,951
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14954502
Author URL: https://archiveofourown.org/users/froggydarren/pseuds/triggeringthehealing
Summary: Stiles’s research spiral sometimes lead to the strangest thoughts. Like now, when he’s wondering about all the things that could possibly glow under UV light, and what it might look like.





	Illuminated

**Author's Note:**

> Written for the [Full Moon Ficlet](http://fullmoonficlet.tumblr.com/) challenge - prompt #280: concede
> 
> Inspired by [this Reddit post](https://www.reddit.com/r/Showerthoughts/comments/8qrdsb/if_semen_glows_under_uv_light_a_penis_ejaculating/) (nsfw)

"There's no way that's gonna work." 

"There's science that..."

"Stiles, it's not going to work," Scott tells him, shaking his head. "There's absolutely no chance."

"Look, logically, it has to work," Stiles says, looking at the screen of his laptop. "I mean—" he turns and rolls away from this desk, then faces Scott. "—crime investigators use blacklists to look for evidence, right?"

Scott nods. 

"And it shows blood, among other things."

Scott nods again.

"It also shows other bodily fluids, and unlike blood, they don't need to be sprayed with luminol, they just glow all by themselves," Stiles continues. "Thus, logic dictates, if you come, and there's UV light, your dick turns into a laser cannon." 

"Dude, I don't want to have the image of your dick shooting glowing semen in my head," Scott tells him and shudders. "Truth be told, I can happily live my life without an image of your dick in general. I'm totally good without that." 

"You'd only see the glowing bits anyway," Stiles says, turning back to his laptop. 

"Still something I don't particularly want to see," Scott mumbles. "If it's even remotely possible. I still think it's not going to work." 

"What's not going to work?" Derek asks, and Stiles yelps at his sudden appearance in the door. 

"Oh fuck, that's it, you need to come with one of those beepers that cars have when they reverse. Or a bell. I can probably get a bell easier," he finishes, his heart slowing down to a normal pace. 

"Not going to happen," Derek tells him, then he pushes off the doorframe and walks over. "What's not going to work? Did you come up with a plan for the harpy yet?" 

"Nope, he fell down a research rabbit hole," Scott answers as he stands up. "Let me know if you figure out something new. Something that's _not glowing_ ," he adds with a pointed look at Stiles. 

"Ass." 

"Yeah yeah, whatever," Scott says, waving his hand absent-mindedly, eyes already on the screen of his phone. 

Stiles sighs, then he turns back to his laptop and reads over the post that got his mind thinking. He's already half-forgotten about the harpy that the pack's been hunting down for the past week, but then Derek clears his throat, and Stiles sighs heavily again. 

"Yes, Derek?" 

"So? Did you find anything?" 

"Only that under UV light, dicks can turn into laser cannons," Stiles blurts, mind still not entirely on Derek's presence in the room.

"What." 

The lack of proper intonation is what gets Stiles's mind to properly register that he's no longer talking to Scott, and he looks up sharply, eyes wide.

"Shit, sorry, random research spiral. Don't mind me," he says, slamming the lid of his laptop shut as he's turning away from his desk. "I got nothing on the harpy. Too much myth and not enough useful information. For once, the internet has been disappointingly useless." 

Derek stares at him. It's not a new or in any way surprising reaction, because Derek tends to do that when Stiles starts to ramble about something completely unrelated to what they're supposed to be talking about. Or even things that are related. In any way, the tiny smirk emerging in the corner of Derek's lips tells Stiles that he's at least amusing, if not helpful. 

His mind is still processing the whole issue of UV lights and bodily fluids, but he's actively trying to push that thought aside, what with Derek and his super sniffer being in the room. Because no, Stiles has had enough pitying (Isaac) and unimpressed (Derek) and occasionally disgusted (Jackson and sometimes Scott) looks directed at him when his libido decided that it's the right time for a dick party. He's got no chance with Derek, no hope of his crush — his dick's crush, really — to come to anything but mild disapproval of Stiles not being able to keep things like his attraction to guys under control. 

So he forces his mind to the current harpy issue, and he turns back to his desk, reaching for the copy of the Argents' Bestiary that he keeps right above his laptop. 

"Wanna look through this? You might be able to spot something that would help us," Stiles says, glancing over his shoulder at Derek, who's still watching him with mild amusement. 

The conversation continues in the direction of research that has nothing to do with UV lights or glowing bodily fluids, and Stiles doesn't think about those things until days later after they've defeated the harpies. It comes back to him though, on and off over several months that follow, despite frequent distractions. One of those things that derail his train of thought a lot is the fact that after one of the pack's battles against yet another thing that went bump in the night, he finds himself not only alone in Derek's loft, but more importantly in Derek's bed. Kissing Derek. Because that's a thing that they're doing. And then some. 

Despite everything else that's happening, Stiles doesn't let go of the thought about how come would look under a UV light, and would he need anything to enhance its luminescence. 

"No," Scott says when Stiles tries to talk to him about it again. "I don't want to know. Anyway, don't you have a boyfriend now whom you could discuss this with?" 

"Well, we don't get much talking done, generally," Stiles mumbles in response, his mind immediately jumping to what they usually do end up doing when together. 

"And I don't want to know about that either," Scott says, then changes the topic to something else. 

-=-=-

It all happens when he's finally put the issue out of his mind for longer than usual. After he and Derek spent time not only talking more but advancing in their make-out activities. Or rather, moved on from making out to what Stiles calls sex. 

"We've already been having sex, Stiles," Derek tells him. "This isn't that big a deal."

"It is for me," Stiles says, curled on his side, Derek's hands wrapped around his torso, come drying on their skin. 

"Okay," Derek concedes. "Then we need to talk about what else is a big deal for you," he adds. "Later. After sleep." 

They do. They talk, they do things, they relish in every free moment they get to spend on mutual handjobs, on blowjobs, and later on fucking each other every chance they get. 

Like the party that the pack decides to throw in the loft after Derek's found a more suitable place to live in town. The loft is perfect for their gatherings, some small and involving only the pack, others... not so much. 

Danny's done a fantastic job organizing a blacklight party, not dissimilar to the one that got invaded by the Oni, the one that Derek had very much not approved of. There are people dancing everywhere, teeth glowing white, speckles of paint all over the place, and some suspicious stains in places Stiles doesn't want to think about too much. At least not while he's busy trying to get Derek to dance with him, with the help of half their pack. 

"I may have miscalculated," he mutters to himself when eventually Erica manages to drag Derek out of his grumpy shell and gets him to sway his hips in ways that get Stiles very much hot and bothered.

It doesn't take long before he joins them on the makeshift dance floor, his own dancing no match to what Erica has managed to coerce Derek into. Still, it gets him close to Derek, it gets Derek's hands on Stiles's hips as he's trying to match their swaying, and it very much also gets Stiles's ass in the close proximity of Derek's crotch. Which in turn leads to Derek leading him away from the crowd, and up the winding stairs to what used to be his bedroom back when he still lived here. At least after he moved the bed from the main area of the loft into one of the smaller rooms upstairs. 

There are several bedrooms, all still with beds and the pack's belongings all over, because they do sometimes use the loft as a home away from home. Derek's room is, however, only sparsely decorated and looks barely lived in — he prefers to head out to his own place unless it's an absolute emergency. That also means that it doesn't have basic necessities — according to Stiles, at least — like condoms and lube, because when they do stay here, it's when the rest of the pack is around too. Werewolf hearing it the biggest cock blocker in the world — Stiles is a lot of things, but neither he nor Derek are too keen on exhibitionism and traumatizing their pack members. 

Tonight though, tonight is different. Because there's a loud party going on downstairs, and that means the noise is loud enough to drown out everything else. Including Stiles's loud moans when Derek decides to rim him until Stiles begs to be fucked. And then the begging that follows. 

The lights are out, and Stiles doesn't mind, even though normally he'd prefer to see Derek's face. But since Derek's behind him it's a moot point anyway and Stiles moans loudly when he feels Derek's dick rub against the cleft of his ass, sliding up and down, head catching on Stiles's rim. 

"Condoms are overrated," he mumbles, sticking his ass up higher to try and signal to Derek that he's all about the barebacking as long as it gets him fucked. 

Derek doesn't move in the direction Stiles wants him to. Instead, he grips Stiles's cock and starts stroking in the same rhythm as he's sliding his own cock between the globes of Stiles's ass, bringing them both to the brink of orgasm faster than Stiles would want to be there. The bass of the music downstairs sets the tempo, and Stiles can't do much more than grip the sheets under his fingers and breathe as his heart races, his balls draw tight, and his whole body trembles from the attempts to stave off his orgasm as much as he can. 

But then Derek's thumb flicks over the sensitive underside of Stiles's dick, and that's it, Stiles falls over the edge and come spurts out of his dick right onto the sheets just as he feels Derek's come shoot across his back. 

He's catching his breath while his body is still trembling a little when he hears the harsh gasp from the doorway. When Stiles looks over, he sees Scott standing there, barely visible in the dim light of a lantern that casts the room into violet light that illuminates Scott's body paint. 

"Okay, point conceded, come does glow under UV light," Scott says into the silence, his voice cracking.  "Not that I wanted to ever find out. Especially not like this. Sorry for barging in, didn't know you guys were here."

From behind Stiles, Derek growls quietly, but obviously loud enough for Scott to hear and to get the message. The door slams closed, and two beats pass before Stiles falls right onto the wet spot on the bed, his body shaking with laughter. 

"Man, I wish I'd seen it," he says, voice muffled by the pillow under his face. 

Derek's heavy sigh is enough to tell him not to pursue that avenue of thought any further. At least not yet. He lets Derek pull him to one side of the bed, and they fall asleep with their fingers intertwined and resting on Stiles's stomach. Before he drifts off completely, he promises himself to try and find a way to see the luminescence that Scott inadvertently walked in on. 

**Author's Note:**

> [my tumblr](http://froggydarren.tumblr.com/) || [my sterek fic tumblr](http://triggeringthehealing.tumblr.com/)


End file.
